Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

re = /(<p>[^<]*\{.*<\/p>)/m str = '<p>While orthotic inserts are able to provide great support and pain relief, they aren’t quite as good as a specialty shoe. Remember that an ill-fitting insert can cause permanent damage and talk to a podiatrist about your foot pain for the best recommendation. Click here&nbsp;if you want to learn more about pain in the foot arch unrelated to plantar fasciitis.</p> <h2>Related Posts</h2> <h2>So What Are These Socks Really Good For?</h2> <h2>Are the bottom of your feet causing you problems?</h2> <h2>A PF Relief Guide</h2> <h2>What is Foot Reflexology &amp; What is it Good For?</h2> <h2>Leave a Reply Cancel reply</h2> <p>Your email address will not be published. Required fields are marked *</p> <p>Name</p> <p>Email</p> <p>Website</p> <p>five &nbsp;−&nbsp; &nbsp;=&nbsp; 2 .hide-if-no-js { display: none !important; } </p><h2>Food For Thought January 2016</h2> <h2>Show Us Some Social Love!!</h2> <h2>Recent Posts</h2> <li> The Climate Pledge of Resistance</li> <li> Green Activism in Boulder, Colorado</li> <li> The Truth About Money and Happiness</li> <li> Why Is There So Much Skepticism About Climate Change?</li> <li> Which Device Would Work Best For You?</li>' subst = '' result = str.gsub(re, subst) # Print the result of the substitution puts result

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html